The growing level of automation in machines and systems has increased the volume of data being transferred, above all in real time. “Industrial Ethernet” is the right and advanced solution to solve this problem. Ethernet technology that has been established on the office environment for many years. The same technology has been extended into the industrial environment down to field level. Products need to meet the requirements of harsh industrial environments. Murrelektronik offers a comprehensive, advanced connector program for these applications .
By Sebastian Richter and Alexander Hornauer
The first Ethernet solutions were developed in the 1970s. These were company-specific solutions with a rather small range, still far away from a general standard. In the 80s, a the first considerations were made regarding a general standard: Ethernet version 1 from the year 1980 and the ISO/DIS-8802/3 standard from 1985 were important milestones. The 100 Mbit/s standard for Fast Ethernet according to IEEE 802.3u from 1995 was a significant step ahead. Today it is the basis for both Ethernet and for Fast Ethernet and it is an established standard for office communication.
In factory automation, automation systems used fieldbus systems, for example Profibus. This became a general communication standard. Both Ethernet and fieldbus systems provided advantages in their applications. However, they were not sufficiently compatible. For a long time, this has prevented a standard communication structure from the office level to the field level. Therefore, transferring the Ethernet standards from the office level into the world of automation (“Industrial Ethernet) was a significant step when implementing global communication systems in companies.
High data transfer rates of 100 Mbit/s (CAT 5 ISO/IEC 11801 Class D) and a transfer method with no collisions make “Fast Ethernet” real-time capable. Management, control and field level are communicating without any perceivable delay, which allows many diverse interesting applications. Remote maintenance of complete installations and systems via company networks or the web are now possible.
The harsh industrial environment at device level (sensor, actuator) requires “Industrial Ethernet” system components to be robust. While IP20 protection (standard RJ45 connetors) is sufficient for components at the office level, the industrial level requires IP65/IP67 protection. Especially important is the high quality of the plug connections: these have to operate reliably against shock, vibration, humidity, EMC problems, temperature fluctuations and at times aggressive media.
D-coded M12 connectors, acc. to the DIN EN 61076-2-101 standard, meet these requirements easily. With 100 mating cycles, IP65/ IP67 and a shock resistance of 50g it became a standard in “Industrial Ethernet”. Using Murrelektronik’s prewired and molded M12 connectors prevents wiring errors and is tamper-proof. The d-coded pin design reliably prevents mistakes caused by wrong connections. A 15°locking mechanism gives protection against shock and vibration and the 360° shielding of Murrelektronik’s M12 connectors ensure reliable data transfer even under extreme conditions.
If the data quantity is higher, for example with High Speed Vision systems, X-coded M12 connectors according E DIN EN 61076-2-109 are the right choice. Four separately shielded data pairs that are separated by an X shaped metal cross, guarantee proper data transfer up to 10Gbit (ISO/IEC 11801 Cat. 6A). Murrelektronik offers the X-coded M12 connectors with a highly flexible PUR cable. This makes these products suitable for moving applications. Combining RJ45 connections in the office and x-coded M12 connections in the field makes it possible to establish a consistent gigabyte communication company wide.
With the Y-coded M12 round plug connector, Murrelektronik offers another interesting type for “Industrial Ethernet” applications. This hybrid solution makes it possible to transfer power and signal together in a single connector. The metal Y-coding separates the four power contacts from the four signal contacts in the pin design. This makes it possible to transfer 100Mbit/s while at the same time providing 2 x 6A power connections. The installations effort in these applications is reduced which enables cost savings. To meet all requirements of the field level, Murrelektronik relies on a PUR cable that is suitable for C-track applications.
For “Industrial Ethernet”, selecting a suitable cable material is as important as choosing the right connector. For each application, a specially designed cable is available. If the wrong cable type is used, cable failure (for example wire break) can occur in a very short time and the complete installation may fail.
For static applications, we recommend cost-effective type A cables with a PVC jacket. For flexible applications, type B cables with a PUR jacket are the right choice with an especially good price/performance ratio. For dynamic applications, where cables are exposed to constant torsion or continuously moving drag chains, a highly flexible type C PUR cable is required. Additionally, it has to be taken into account that an Ethernet cable that is suitable for C-track applications is not a torsion cable and a torsion Ethernet cable is not suitable for drag chains. It is also very important to pay attention to the minimum bend radius, because using a small radius will destroy the cable.
Murrelektronik offers the right cable for every application. To ensure a maximum lifetime, decisive criteria regarding the application has been defined such as minimum bend radius, degree of torsion, bend cycles and other parameters, and have been confirmed in many tests.
Murrelektronik’s “Industrial Ethernet” cables are resistant to external interference which is ensured by the visual shielding of at least 85 percent together with the 360° shielding concept of the connector. This ensures stable and proper data transfer.
Murrelektronik offers a comprehensive product range for “Industrial Ethernet” as a standard program that is complemented by user-specific and customized versions. The right cable is available for all application specific protocols that were developed on the same physical basis (for example: PROFINET, Powerlink, EtherCAT…). Shielded M8 connectors have been established for EtherCAT. SERCOS III can be recognized by its special red Cat.5e cables, suitable for drag chains. The AIDA work group (Automation Initiative of German Automobile Manufacturers) defined the push pull power and push pull data connectors (copper and optical fiber) as standard for PROFINET.
Appropriate interface modules such as flange connectors or cable entry systems and the corresponding bus cables sold by the meter from 100m to 500m – (all cables are UL-approve) complement this product range. All these cables are suitable for Fast Connect and can easily be pre-wired with the Fast Connect tool.
With experience from many different industries and a comprehensive product range, Murrelektronik is a strong partner for companies that want to create consistent networks based on “Industrial Ethernet”.